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I was thiking of installing a video system on my airplanes and heli for some years now and reading this forum I decided it's time to go ahead and do it.

I spend most of the day reading product descriptions and I have a really hard time deciding which frequency band I should use. At www.rcdon.com website I read that after a lot of testing he concluded that 900Mhz does the job better (his long range-high altitute video footage shows no glitches at all!), supercircuits also state that 900Mhz have a better range and "handle better the various obstractions".

Also from my experience (with long range wi-fi links) the 2.4Ghz band has a lot of noise the last few years (mainly due to the recent popularity of the Wi-fi systems, DECT phones). Still most of you here, as far as I can tell, are using the 2.4 band, which is something I would also like to do since I already have a lot of hardware (amps, commercial patch, yagi, rubber duck antennas, etc).

My ultimate goal is to fly the aircrafts through the camera and not just around myself at 100m distance, so link reliability is a priority. I am also concerned with the 900Mhz since here in europe we have the GSM phones in an adjacent frequency. My father that flies with me is a licenced amateur radio operator so law is not a problem.

What are your experiences, thoughts, suggestions?

Thank you,

Dimitris, Greece

PS: Also will the Seagull telemetry system from Eagle Tree cause interfearance to a 900mhz video system? - it transmits at 900 too.

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Well the reason I did not reply is because I have no idea what the conditions are like in grease. If you were in the UK I would say go 2.4Ghz at 10mW if you want to be legal and 200mW if you want good range the easy way. 900Mhz is no go here.

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why is 900Mhz is a no go in the UK? Is it a legal reason or interference make it useless?

The situation in Greece right now is that everybody is buying Wi-fi devices and noise in 2.4Ghz skyrocketed the last years (I see 10X more noise all over the band than 5 years ago when I first got involved in the wireless networks). With my laptop's internal low gain antenna I can receive at least 40 wireless access points sitting on my desk! Not to mention those long range links on the roof tops... they crank up the wattage of cheap access points through firmware upgrades, install a high gain omni and "leak" RF pretty much everywhere.

Back to video transmission: My only experience is at home with three different 2.4Ghz TX/RX sets that I bought in order to watch my PCs video in the livingroom is that none of them are practicaly working at 20m distance! They work perfectly in my summer home which is in the middle of nowhere though. Of course these are cheap chinese transmitters/receivers but the results make me reluctant to believe that 2.4 is a reliable band for this application now days in urban/suburban areas.

I think also Mr.RC-Cam mentioned somewhere here that 2.4 at his local flying field is not working like it used to.

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As Kilrah said cell phone use is the reason its no go here. 1 it would invite interference and 2 you would get jumped on as you would get reported for sure by the phone service providers. On 2.4Ghz here if you are away from a built up area you can get away with using a bit more power as nobody will even notice.

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In Greece you may have an option of 868 Mhz, because it does match european bands assignements. Here in Russia we have only a 2.4 Ghz for amateur use in fact 900 Mhz is cellular, and 868 is a legacy government frequency

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I saw those modules a while back as LPRS send me emails about once a month. I was put off as they are stereo and all my other gear is mono. I would like to see any pictures of your gear if you can post thm here though. I may give them a go...

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Stevie, the problem for me is I dont use them as a pair as I have lots of TX and RX set ups that I mix and match depending on the plane and application. I have some RX modules built on to the back of the aerials so it would be hard to swap them all now.